Drifting control valve



Oct. 3, 1944. L. B. JONES 2,359,647

DRIFTING CONTROL VALVE Filed April 50, 1942 s Sheets-Sheet 1 m WITNESSES: g g INVENTOR;

z/gwyaw Zlqydfi- M Oct. 3, 1944. JONES 2,359,647

DRIFTING CONTROL VALVE Filed April 30, 1942 3 Sheets-Sheet 2 W1 TNESSES; INVENTOR;

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Oct. '3, 1944.

DRIFTING CONTROL VALVE JONES Filed April 30, 1942 '3 Sheets-Sheet 5 INVENTOR: ZioyzhiJwzes,

' ATTORNEYS.

W1 TN ESSES Patented Oct. 3, 1944 UNITED STATES PATENT OFFICE DRIFTING CONTROL VALVE Lloyd B. Jones, Hollidaysburg, Pa.

Application April 30, 1942, Serial No. 441,098

16 Claims.

This invention has general reference to means for controlling the admission and exhaust of motive fluid to and from the cylinders of reciproeating engines; and more particularly relates to locomotive fluid distribution systems wherein individual poppet valves serve for admitting and exhausting steam to and from each cylinder, although the instant improvements are not necessarily restricted to such systems.

One of the inherent advantages of the subdivision of function to individual poppet valves in the fluid distribution systems of locomotives, more particularly, is the opportunity afforded for holding the exhaust poppet valve closed while "drifting and thereby prevent in-drawing of smoke, gases and cinders from the smoke-box, through the exhaust space into the engine cylinders.

In order that full benefit may 'be had of the noted advantage it is essential that the exhaust poppet valve be held closed, while circulation of a sufliciency of the motive medium should take place, through the engine cylinders, to overcome frictional resistance of the relatively moving part while drifting.

The primary aim of this invention is to furnish a drifting control device which ensures positive attainment of the advantages recited in the preceding paragraph.

Another aim of this invention is the provision of an automatic drifting control device including a differential piston having a directly-associated double-seating release valve, preferably for operation in combination with the fluid-actuated poppet valve of reciprocating engines.

A further aim of this invention is to provide a drifting control valve for application to steam locomotives which is comparatively simple in construction, automatic in action, and comprises but few parts.

For the purpose of illustrating this invention, there is shown by the accompanying. threesheets of drawings a typical embodiment which is, at present, considered to be preferable, since such will give in practice satisfactory and reliable results; although it is to be understood that the combination of instrumentalities which said embodiment includes may be otherwise arranged and organized with corresponding advantages, hence the instant disclosure is not to be construed as limitative other than reasonable interpretation of the concluding claims requires.

In the drawings:

Fig. 1 is a fragmentary sectional view of one end of an engine cylinder having an arrangement of admission and exhaust poppet valves, substantially in accordance with applicants prior Patent NO. 2,260,458, dated October 28, 1941, on LO- comotive steam distribution system, and also including the drifting control device of the instant invention, as an auxiliary, with the associated connections to the engine cylinder admission and exhaust poppet valves.

Fig. 2 is a longitudinal section through the drifting control device of Fig. -l,- drawn toa larger scale for better illustration of structural details, and with the movable parts in the position they occupy under normal running conditions of the locomotive.

Fig. 3 is a similar section to the preceding fig-- ure, but showing the movable parts as located when the locomotive is drifting.

Fi 4 is a transverse section on the arrowed plane IV-IV of Fig. 2.

Fig. 5 is a similar section on the plane V V of Fig. 2; and,

Fig. 6 is a cross-section on the staggered plane VIVI in Fig. 3.

In describing the form .of this invention exemplified by the above captioned drawings, specific terms will be employed for the sake ofclarity, but it is to be understood the scope .of said invention is not thereby.limited,-each such term being intended to embrace all reasonable equivalents which perform the same function for an analogous purpose.

.Referring more in detail to Fig. ,l of the drawings, the reference character 9.designates a frag, mentary portion of a'locomotive engine cylinder having an associated steamchest l0, and exhaust passage II. The steam chest in is provided with admission poppet valves l2 havingacompanion pilot-valve I3, while the passage H is similarly equipped with an exhaust poppet valve .l4 and allied pilot-va1vel5; said pilot-valves l3, l5 beingshiftable by push ,rods I5, I1, respectively, under actuation of .amaster controlling cam 18: all substantially in accordance with the disclosure of the patent hereinbefore referredto, and they are merely referredto by way-of affording suitable background in explaining the illustrated device of the present invention, which is compre hensively identified by the numeral l8, the same being well adapted for attainment of the objects specified.

The drifting controlvalve or device |.9,..as best shown byFigs. 2-.6- inclusive, comprises twomain, or a lower and an uppenhollow casing compo- 'nents 20, 21 respectively; the formerifl of which embodies a supporting flange 22, see Fig. 6 only,

whereby said valve is attachable to any rigid part of the locomotive, not shown: while said casing components 20, 2| are preferably connected together in axial alignment by a screw-thread joint 23.

The casing component is closed-in by a bottom wall 24 having a screw-threaded aperture 25 for attachment of one end of a pipe connection 23, correspondingly secured at 21 into the exhaust passage H, see Fig. l. Inaddition the casing component2f| includes diametricallyopposed apertures 28 for threaded connection of pipes 29, 30, the former 29 leading to the admission poppet valves |2 at .the front end of the cylinder 9, and the latter 30 similarly communicating with admission poppet valves-not shownat the back end of said cylinder, as readily understood by those conversant with the art; while the bore of the casing component 2|! is, preferably, fitted with a friction reducing liner 3|. 7 r Secured by threaded-connection 32, to the up- .per end of the valve component 2|, is a polygonally-shaped cap 33 affording axial attachment, by;a,nipp le 34, fora union-elbow 35, in turn having pipe connection 36 into the steam chest at any desirable: point, not indicated, so that when the locomotive throttle is opened, pressure from said chest also enters the control device |9,.'as well as the poppet valves l2, for a purposejlatelf explained.

a Within the drifting control device l9 and movable in the liner 3| of the casing component 20 is a differential-piston 31, preferably of stain- .less steel to eliminate sticking due to corrosion;

while a double-seating release-valve 38 operates 7 to. the fact that the piston 31 has the solid por- Ition 43, beyond the hollow section 42, slightly reduced to define a bevel 44 for. engagement with a complemental seat, or flare, 45 in the bore .46 of the liner 3|; while a proximately-related circumferential groove 41 has an inclined continuously open drain duct48 connecting into an axial bore 49' of the solid portion 43; said duct serving to permit any'condensation collecting in the groove 41, when the piston valve 31 is seated :as' shown in Fig. 2, .to drain into the exhaust 25. .In addition the solid portion 43 is provided with a surrounding recess 50; while the outer surface of .the hollow section 42 is appropriately grooved at -5|, to reduce friction. The differential'piston .31 it is to be particularly remarked embodies a .minor differential area which is made by the difference between bevel seats 44 and 45 and the ton 31 of reduced diameter intermediate the bevel 44 and the lower part of said piston including the grooves 5|, plus the circumferential groove 41, see Fig. 3 to best advantage.

Referring again to the valve component 2| ,which, is preferably, of polygonal formation excepting for the screw-threaded end that receives the cap 33; the same embodies a lateral orificed branch 52 for attachment of one end of a pipe 53, connecting into the cylinder exhaust passage H at 54, Fig. 1; while it is to be observed the central portion of the transverse wall 4| is thickened and suitably shaped to define a bevel-seat 55 for the complementally-fiared lower end 56 of the release-valve 36; whereas an annular series of apertures 51 are provided through said central portion. ther remarked, the upper portion of the compo-" nent 2| is conveniently drilled, before finishing interiorly, to provide a series of equally spaced longitudinal grooves or flutes 58 terminating at the inner ends proximate a beveled shoulder 59, referably, outwards relative to the exhaust connection 52 and wall 4|. It will also be apparent that When the valve 38 is in the up position of Fig. 3 it would be sealed were the flutes 58 not provided; while said flutes are necessary to accommodate pressure around the top portion of the piston 31, and to also serve as guides for the valve 38 when moving up and down.

The release-valve 38 is, preferably, of the hollow formation, best understood from Fig, 3; that is to say, it is of approximately concavo-convex longitudinal section with an apertured wall 60 near the lower end 56, said wall having serially arranged holes therethrough and inclined relative to the longitudinal aXis of the valve 38 to define ports 6| affording flow-communication from the upper side thereof to the correspondingly spaced apertures 51 in the transverse wall 4| of the casing component 2|. .It is to be also observed that, in addition to the flared lower end 56, the release-valve 38 is provided with an axially-spaced or upper differential flare 62, for

seating-engagement on the beveled shoulder 59,

in the valve component 2|, when said valve is in the lower or closed position of Fig. 2.

From the above explanation of the structural features of the combination differential-piston 31 and double-seated release valve 36, it will be readily understood by those conversant with the art that, when the enginethrottle is opened, steam pressure from thechest l0 enters the device '|9 by way of the pipe 36and elbow 35, with flow into the fluted portion58 of the casing component 2| and flaring upper part of the seated release-valve 38; and by passage through the inclined ports 6| and apertures 51' will exert pressure in the hollow section 42 of the piston 31, whereby the latter is forced away from abutment with the wall 4|, or downwardly, as shown in Fig. 2. This downward movement of the piston 31 is resisted by steam, admitted through a rectangular port 63 and pipe'connection 64, Fig.

11, from a separate source, preferably the locomovare in flow communication, by way of registering ports 65 inthe liner 3| and piston recess 50, with the pipe 26 into the exhaust passage whereby the central differential portion of the admission poppet valves |2 are connected to-said exhaust passage; in accordance with the disclo- It is'to be fursure of the prior patent hereinbefore referred to. On the other hand, when the drifting-valve piston 31 is in the up position of Fig. 3, boiler steam is being admitted to the pipes 29 and 69 from the port 63 with the ball valve 66 on its lower seat thereby sealing the steam chest open. When the locomotive is under normal operation the piston 31 is in thedown position of Fig. 2, the pipe 29 is sealed against boiler steam, by its bevel 44 engaging the seat 45, and said pipe will then be in communication with the auxiliary port 25 and exhaust pipe 26; whereby the differential cavity of the admission valve 14 is connected with the exhaust. Similarly when the locomotive throttle is normally open steam chest pressure I admitted under the ball valve 66 by way of a port I, leading from the steam chest l0, Fig. 1, holds said valve firmly against the upper seat, while no live steam from the boiler is admitted to the pipe 29 inasmuch as the piston 31 is sealed or down so that communication between the port 63 and the pipe 29 is thereby sealed.

When the locomotive throttle is closed and the pressure inthe steam-chest l0 drops to somewhere between ten and twenty pounds, as aforesaid, the piston 31 is driven upward by the boiler pressure entering from port 63 with flow through groove 41, into the differential area between the bore 46 and the flare 45 in the liner 3|. At the same time, upward movement of the piston 3'! lifts the release-valve 38, thereby venting the contained steam-chest pressure through the outlet 52 and pipe 53 to the engine cylinder exhaust passage l l, as readily understandable from Figs. 1 and 2. When the piston 31 is in the up-position, shown by Fig, 3, it will also be observed that the port 63, connects with the respective passages 28 and associated pipes 29, 30, whereby boiler pressure steam is conducted to the admission-poppet valves [2. Such boiler pressure steam is also admitted from the respective pipes 29, 30, by way of a branch 68, to the associated ball check-valve66 and thereby forces the latter to its lower seat 10, thus closing the passage H from the steam-chest ill by way of the port It). This boiler pressure steam being now admitted to the exhaust pilot-valve l5 may do either one of two things, depending on the position of the main locomotive reverse gear, not shown, but well known to those conversant with the art, or on reference to the previously mentioned patent. If the reverse gear lever be left in forward running position while the locomotive is drifting, the pilot-valve l5 will continue to operate in synchronism with the main or cylinder piston 12, Fig. 1, and thereby deliver steam pulsations to the exhaust-poppet piston 13, which means that the exhaust poppet valve M will always be closed whenever the cylinder piston 12 moves away from said poppet valve l4, whereby smoke and exhaust gases are effectively prevented from following said cylinder piston. Should the locomotive reverse lever be placed on dead center while drifting, which is the preferable position, the exhaust pilot-valve I5 will not receive any impulse from the operating cam 18 and said pilot-valve will remain closed, thus admitting boiler pressure steam continuously on top of the poppet piston 13 and thereby hold the exhaust-poppet valve I4 closed. With the pilot valve 15 controlled by the valve gear as stated, the pressure admission to the top of the differential valve 13 will be intermittent due to the afore stated action of the pilot valve; but there is no pressure tending to raise said differential valve because the ball-check 66, under these conditions, will be on its bottom seat, which seals the passage H from the steam chest I0 and also seals the passage to the difierential cavity in the difierential valve. Furthermore, there is no pressure acting on the bottom of differential valve 13 because the steam underneath it is cone nected to the exhaust passage l I at all times. It will be further seen that boiler pressure steam being also admitted to the differential or central portion 14 of the piston 15 of the admission-poppet valves I2 as indicated by the arrowsat the right hand of Fig. l, the latter will be heldin the upward or open position; and, even though the admission pilot-valve l3 continues to receive impulses from the associated cam IS, the steamchest l0 having been vented to the exhaust passage H through the release-valve 38, as before explained, there will be no steam-chest pressure available to act downwardly on the admissionpoppet valve pistons 75. Incidentally, it is to be here remarked that complete venting of the steam-chest ll does not actually take place so that when the admission valve piston 15 is held up or open there remains a sufficiency of steam in said chest for circulation through the cylinder.

9 and associated parts, as readily understandable on an examination of, the right-hand portion of Fig. 1, to overcome frictional resistance of the relatively movable parts when the locomotive is drifting.

The just explained operative conditions continue as long as the locomotive throttle remains closed, and any slight amount of leakage from said throttle-valve is vented through the releasevalve 38, thereby preventing pressure from building up in the steam-chest l0 and causing the admission-poppet valves 2 to assume any position other than determined by the drifting control device I9.

On the other hand, when the locomotiv throttle is opened, steam entering the chest ID at first tends to escape through the releasevalve 33 to the exhaust passage H, but the exhaust outlet 52 and pipe connection 53 to said passage are purposely made considerably smaller than the steam-chest connection 36, so that a choke occurs, whereby the large volume of steam coming from the main throttle almost instantly forces the control-valve piston 37 down and closes the release-valve 38. The release-valve 38 being hollow, as hereinbefore explained, the steam coming from thechest I0 through the pipe 35 and union-elbow 35 passes through said hollow by way of the inclined ports BI and apertures 5'! and exerts its pressure on the piston 31, to hold said piston down firmly to the seat flare 45 in the liner 3!, as clearly shown in Fig. 2; and, in this position, it will be also evident that the boiler pressure steam-flow from the rectangular port 63 entering the circumferential groove 47 will be trapped therein in opposition to the steam chest pressure, while the outlets 25, 52 are again open by way of the connections 26, 53, respectively, to the exhaust H. At the same time, exhausting of steam from the flow pipes 29, 3G and the admission of steam-chest pressure to the exhaust pilot-valve 55, by way ofthe passage v68, causes the ball check-valve 66 to be forced upward against the seat 67 and thereby prevents steam-chest pressure passing from said passage 68 into the branch 69 and flow pipes 29,. 30.

From the foregoing it is considered the merits and advantages of'th'e' disclosed invention will set forth what is deemed to be a preferred combination and arrangement of, parts for the attainment of the referred to objects, this invenpoppet valves for individual admission and extion is not limited thereto as there might, ob-

" viously, be changes made in the form, 'condeparting from the spirit of said invention as comprehended Within the scope of the following claims.

Having thus described my invention, I claim:

1. -A control device for steam locomotive cylinders having admission and exhaust valves; conduit means included in the locomotive throttling system for supply of steam chest pressure to the device; conduit means for supply of steam, from an independent source and at a different pressure to the control device; means including a differential piston and a coactive relief valve; and associated mean operative by the difference in pressure between said supplies of steam to hold the cylinder exhaust valve closed during drifting of the locomotive.

. 2. In a locomotive engine having driving cylinder, steam chest and exhaust provisions, poppet valves for individual admission and exhaust of steam to and from both ends of the cylinder, and associated pilot means controlling opening and closing of said poppet valves; the combination of a drifting control device including a, differential-piston and an aligned release valve, flow means for conducting steam chest pressure to the control deviceto force the differential piston in one direction, means affording flow connection from another source of similar pressure steam to the device for effecting reverse movement of the differential piston and opening of the release-valve with simultaneous holding of the cylinder admission poppet valves open, and means for diverting pressure from the flow connection aforesaid to the exhaust pilot means for holding the associated poppet valve closed during movement of the engine cylinder piston away from said poppet valve when the locomotive is drifting.

.3. In a locomotive engine having driving cylinder, steam chest and exhaust provisions, poppet valves 'for individual admission and exhaust of steam to and from both ends of the cylinder, and associated pilot valves controlling opening and closing of the respective poppet valves; the combination of a drifting control device including a differential-piston and an aligned coactive double-seating release-valve;

means for conducting flow of steam chest pressure to the control device to force the dinerential-piston in one direction, means for supplying pressure from another source of steam to the control device for opposedly moving the difierential-piston with opening of the releasevalve; means for efiecting concurrent closure of during drifting of the locomotive.

4. In a locomotive engine having driving cylinder, steam chest and exhaustprovisions,

haust of steam toand from both ends of the cylinder, and associated pilot valves controlling opening and closing of the respective poppet valves; the combination of a drifting control device including a differential-piston and a coactivedouble-seating release-valve; means for conducting flow of steam chest pressure to the control device to force the differential-piston in one direction; means providing outlet connection from the control device to the cylinder exhaust; means for conducting pressure steam from another source of supply to the control device for opposedly moving the difierentialpiston. and concurrently opening the releasevalve; and a connection, from the second mentioned source of steam pressure supply, including a check valve operative to concurrently divert pressure from said supply, to the top of the exhaust poppet valve, for effectively holding said poppet valve closed, during movement of the engine cylinder piston away, therefrom, when the locomotive is drifting.

5. In a locomotive engine having driving cylinder, steam chest and exhaust provisions, poppet valves for individual admission and exhaust of steam to and from both ends of the cylinder, and associated pilot valves controlling opening and closing of the respective poppet valves; the combination of a drifting control device comprising a difierential-piston and aligned double-seating release-valve, a pipe for flow of steam chest pressure to the control device for forcing the difierential-piston in one direction;

an outlet connection from the control device to the cylinder exhaust; a pipe supplying pressure steam from another source to the control devicefor opposedly moving the difierential-piston with concurrent opening of the release-valve and closure of the cylinder exhaust poppet valve when the steam chest pressure reduces to a low amount; a branch connection from the second mentioned pipe to the exhaust poppet valve; and an associated double-acting check means serving, when in one position to divert flow of pressure steam from said branch connection to the exhaust poppet valve and thereby effectively hold the latter closed.

6. The combination of claim 5, wherein the outlet connection from the control device to the cylinder exhaust is of considerably smaller size than the inlet pipe for admission of the steam chest pressure, said outlet connection creating a choke in the control device effective to seat the release-valve, and concurrently shut off the pressure steam from the second mentioned source of supply.

7. The combination of claim 5, wherein the double acting check means is in the form of a ball valve coactive with spaced seats, one ofsaid seats having connection with the pressure flow pipe for the second mentioned source of steam supply, and the other seat being in flow communication with the cylinder steam-chest.

8. The combination of claim 5, wherein the release-valve is of ported formation to facilitate flow of steam chest pressure to the major area of the differential-piston, and the minor area of said piston is defined by an end reduction of said piston including a circumferential groove.

9. The combination of claim 5, wherein the differential-piston is provided with an annular recess, and the control device has opposed'con nections to the cylinder admission and exhaustpoppet-valves for flow of pressure steam from the second mentioned source of supply thereto, when the locomotive is drifting, to hold the admission poppet valves open and the exhaust poppet valves closed.

10. The combination of claim 5, wherein the bore of the control device is provided with an inner annular shoulder for limiting the down movement of the differential-piston, and the said device and piston embody means for flow of pressure steam from the second mentioned source of supply through the control device, when said piston is moved away from the shoul der aforesaid.

11. A drifting control device comprising aligned casing components having a cap at one end with means affording flow communication from a source of pressure fluid, an outlet from said device to exhaust, means in the device defining spaced seats with a series of apertures through one of said seats, a hollow release valve embodying portions for joint coaction with said seats and an axial stem slidable through a complemental orifice in the adjoining seat, a wall across the release valve having a series of ports therethrough in correspondence with the seat apertures, fiow connections to the device aifording communication from the source of pressure.

fluid, a differential-piston movable in the device under the influence of motive-fluid supplied from a separate source of pressure,-and said piston also serving to open the release valve for venting of the pressure fluid acting thereon.

12. A drifting control device comprising vertically-aligned and detachably connected upper and lower casing components having a cap at the top and a closure wall at the bottom, means affording flow communication through the cap from a source of pressure fluid, an outlet from the upper component to exhaust, means in said upper component defining vertically-spaced seats, an annular series of apertures through the lower seat, a hollow release-valve embodying portions for coaction with said seats and an axial stem slidable through a complemental bore in the lower seat of the upper casing, a wall across the release-valve having a series of ports in correspondence with the, lower seat apertures, opposed connections to the lower casing component affording flow communication from the source of pressure fluid aforesaid, an outlet connection from said lower casing component to exhaust, a differential-piston movable in the bore of the lower casing component under the influence of motive-fluid supplied from another source of pressure, and said piston also serving to lift the poppet release-valve for venting of the pressure acting thereon.

13. A drifting control device as defined in claim 12, wherein the upper casing component embodies a transverse wall with the central part shaped to define a bevel seat, said seat having a surrounding series of apertures therethrough, the upper portion of the bore of said component being longitudinally fluted to afford guidance for the release-valve, a beveled shoulder adjoining the inner ends of the fluting to provide the upper vertically-spaced seat, and a lateral branch intermediate said seats affords connection to exhaust.

14.- A drifting control device as defined in claim 12, wherein the hollow release-valve is of approximately concavo-convex longitudinal section, spaced flares circumferentially around said release-valve coact with the upper casing component seats, a transverse wall adjoins the inner end of the release valve, said wall having a central guide stem extending outwards therefrom, and a series of ports through said wall, said ports being circumferentially-spaced around the wall and inclined relative to the longitudinal axis of the valve.

15. A drifting control device as defined in claim 12, wherein the lower casing component embodies diametrically-opposed lateral branches for pressure flow-connections and an outlet in the bottom wall for exhaust, a rectangular port in the casing component wall serves for connection to another source of in-flow pressure, an anti-friction liner in the bore of said component, and said lower casing component includes a flange whereby the control device is attachable to stationary structure.

16. A drifting control device as defined in claim 12, wherein the differential-piston comprises a hollow-section to define the major effective area and a diametrically-reduced and relatively shorter solid extension, with an intervening circumferential bevel defining a minor effective area, an axial bore in said solid extension, a circumferential groove around the solid section, an inclined duct provides drain connection from said groove to the inner end of the solid section axial bore, and a substantial recess surrounds the solid extension.

LLOYD B. JONES. 

